1. Field of the Invention
This invention relates to multi-textured snack chips, particularly potato chips, prepared from a dry starch material mixed with moist starch agglomerates. The invention also relates to a process for making the snack chips.
2. Description of the Related Art
Conventional potato chips have an initial crisp texture, but they become soft after chewing and lose their crunchiness. Kettle-type potato chips retain their crunchiness during chewing, but their initial texture is undesirably hard for most consumers. The conventional and kettle-type potato chips are both structurally and texturally homogenous within a given type of chip.
U.S. Pat. No. 2,665,208 to Spieser, issued Jan. 5, 1954, discloses a method of making foodstuffs by first cooking potatoes without adding water, then mixing in a dry starch, then working the mixture into a homogeneous mass, and then forming the mass into pieces which are fried in oil. A homogeneous mass of dough will produce products that are homogeneous in texture.
U.S. Pat. No. 3,835,222 to Wisdom et al., issued Sept. 10, 1974, discloses a process for producing potato chips that are homogeneous in color, texture, flavor, solids content, and oil content. After a potato dough is made, it is admixed with other starch containing materials such as rice flour, tapioca flour, or potato starch. However, water is added along with the starch material and the ingredients are mixed into a homogenous, hydrated mass before being formed into chips and fried in oil.
U.S. Pat. Nos. 3,886,291 and 3,997,684 to Willard, issued May 27, 1975 and Dec. 14, 1976, disclose fried potato snacks prepared by mixing cooked potato solids with raw potato starch, adding water to form a dough, extruding pieces from the dough, and frying the pieces to form an expanded fried potato snack. The fried potato snacks have a relatively porous internal structure encased in a continuous relatively dense exterior surface layer of fried potato solids, not a texture having discrete crisp regions intermixed with discrete crunchy regions throughout the snacks.
U.S. Pat. No. 4,293,582 to Hamann et al., issued Oct. 6, 1981, discloses a potato dough for making french fries, made from 45-75% cooked, mashed potatoes, 9-20% dehydrated potato flakes, 0.12-2.0% liquid oil, and 17-27% aqueous slurry including a binding agent. The mashed potatoes, liquid oil, aqueous slurry, dry ingredients and potato flakes are mixed together to form a dough, then the dough is kneaded and formed or extruded into the desired shape for frying. This process will not produce a product having discrete regions of crisp texture and discrete regions of crunchy texture.
U.S. Pat. No. 4,752,493 to Moriki, issued Jun. 21, 1988, discloses expanded hollow snacks made from a dough containing a mixture of "farinaceous raw material having small swelling capacity" (e.g., wheat, rye, maize, rice) and "farinaceous raw material having large swelling capacity" (e.g., potato, tapioca).
U.S. Pat. No. 4,834,996 to Fazzolare et al., issued May 30, 1989, discloses a baked snack food made from a dough containing a starch such as potato, corn, rice, tapioca, or wheat. Dough pieces are baked in a conventional oven, during which time the exterior layer of the dough is said to cook rapidly and trap steam in the interior portion of the dough.
U.S. Pat. No. 4,861,609 to Willard et al., issued Aug. 29, 1989, discloses fried expanded snack products made from a dough containing: (a) finely divided starch-containing solids such as potatoes, corn, wheat or rice which are mixed with water; and (b) dry cracked cereal grains having a particle size larger than the average particle size of the finely divided starch. The larger particles act as vents to allow steam to escape, thereby reducing undesirable puffing of the snack during frying. The product will not have sizable discrete regions of crisp texture and crunchy texture.
European Patent Application 0,324,460 of Willard et al., published Jul. 19, 1989, discloses fabricated snack chips made from a dough which is treated by exposure to an airstream or heat so as to create a moisture differential between the treated surface of the dough and its interior. This treatment is said to control the amount of surface bubbling of the chips when they are fried.
Danish Patent Application 3709-625-A, published Mar. 24, 1987 (Abstract), discloses a dough for preparing chips made from flour, water, salt, eggs, and dry potato.
Netherlands Patent Application 8402-019-A, published Jun. 26, 1984 (Abstract), discloses a potato-based food product made from pre-cooked and modified starch mixed with dehydrated potato flakes.
The above-described patents do not disclose a method of making snack chips having discrete regions of crisp texture and crunchy texture within a chip, so that the snack chips provide an initial crisp texture with a continued crunchy texture after chewing. Neither do the conventional or kettle-type potato chips provide these advantages.